Gil Hyatt

need some help. I have a pettit intake, pulleys, DP, Mid pipe and exhaust. Plus the pettit upgraded ecu. I continually make 12lbs to 4500rpm and then drop to 8 and stay there.. Why would i not be going back up to 12 after 4500? Any help or just a quick search topic on this would help greatly..
Thanks

rx7machine

All I know about this is that the boost of a stock FD is suppose to 10-8-10. At least I think that's what it's suppose to be..

Gil Hyatt

Yes, you are correct on that pattern, from what I understand. However with the mods that I have I should be getting 12lbs or more but I'm just trying to understand why I drop to 8lbs and never get back to 12?

rx7machine

Maybe a boost spike.. I'm not sure what causes it though.. Still stock twins? Maybe that has something to do with it.

Bucrx7

I'm surprised you're not getting any boost spike with an open exhaust. When was the last time work was done to your car? What was the pattern before the work was done?

Gil Hyatt

I am also surprised.. I was expecting a 15lb spike or more.... that is why I have the pills on standby in order to regulate.... But i never had used them because boost never creeped up beyond 12lbs.??? It jumps right up to 12 before 4500, but goes to 8 and stays...... Do you think my exhaust is letting the 2nd turbo spool up too quick and then not letting it get up to 12 lbs. The turbos feel fine... I have the pettit cold air intake... etc. etc as i listed above..... No one has done any boost mods.... besides myself.. I put the downpipe and midpipe on and installed the pettit ecu.. Do you think the ecu is restricting the fuel? I would like to fix this.. any help is greatly appreciated.... Thanks...